Linear acceleration responsive switch



July 27, 1965 POPE 3,197,587

LINEAR ACCELERATION RESPONSIVE SWITCH Filed May 9. 1961 8 Sheets-Sheet 1 FIG-l INVENTOR. KENNETH E. POPE ATTORNEY July 27, 1965 K. E. POPE LINEAR ACCELERATION RESPONSIVE SWITCH 8 Sheets-Sheet 2 Filed May 9, 1961 INVE KENNETH E. PO

ATTORNEY y 1965 K. E. POPE LINEAR ACCELERATION RESPONSIVE SWITCH 8 Sheets-Sheet 3 Filed May 9, 1961 MHOE v MOT m o N INVENTOR. KENNETH E. POPE ATTORNEY y 1965 K E. POPE LINEAR ACCELERATION RESPONSIVE SWITCH 8 Sheets-Sheet 4 Filed May 9, 1961 R.E 0P mm w W 8 IH I /Q m 9 K M t J B a n w F 1% k 3 M 2| L MW 1 6 3 M ATTO R NEY y 1965 K. E. POPE LINEAR ACCELERATION RESPONSIVE SWITCH 8 Sheets-Sheet 5 Filed May 9. 1961 INVENTOR. KENNETH E. POPE WWW ATTORNEY July 27, 1965 K. E. POPE LINEAR ACCELERATION RESPONSIVE SWITCH 8 Sheets-Sheet 6 Filed May 9, 1961 INVENTOR. KENNETH E. POPE BY MfW ATTORNEY July 27, 1965 K. E. POPE LINEAR ACCELERATION RESPONSIVE SWITCH 8 Sheets-Sheet 7 Filed May 9. 1961 ENVENTOR.

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KENNETH E. POPE July 27, 1965 K. E. POPE 3,197,587

LINEAR ACCELERATION RESPONSIVE SWITCH Filed May 9, 1961 8 Sheets-Sheet 8 8 m FIG 23 United States Patent 3 197 587 LINEAR AQCELERAT IOIi RESPONSIVE SWITCH Kenneth E. Pepe, Albuquerque, N. Mex., assignor to Globe Indusnies, Inc, Dayton, Ohio, a corporation of Ohio Fiied May 9, 1961, Ser. No. 168,821 13 Claims. (Cl. zen-615s I switch of the invention,

FIGURE 2 is a cross-sectional view taken along line 22 of FIGURE 1,

FIGURE 3 is a partial cross-sectional view similar to FIGURE 1, but indicating the re-setting operation,

FIGURE 4 is a cross-sectional view of a portion of FIGURE 2, taken in the plane of FIGURE 1, showing the locking cam,

FIGURE 5 is a cross-sectional view similar to FIGURE 4, but showing the locking cam in closed position,

FIGURE 6 is a view similar to FIGURE 1 showing a two-switch arrangement,

FIGURE 7 is a cross-sectional view taken along line 7-7 of FIGURE 6,

FIGURE 8 is a cross-sectional view similar to FIGURE 1, but of a modification of the switch of the invention,

FIGURE 9 is a sectional view taken along line 9-9 of FIGURE 8,

FIGURE 10 is a sectional view taken along line III-10 of FIGURE 8,

FIGURE 11 is a sectional view taken along line 11-11 of FIGURE 8,

FIGURE 12 is an end view of the re-set cam plate of the embodiment of FIGURE 8,

FIGURE 13 is a left side view of the cam plate of FIGURE 12,

FIGURE 14 is a right side view of the cam plate of FIGURE 12,

FIGURE 15 is a side view of one switch plate shown in FIGURE 8,

FIGURE 16 is a side View of shown in FIGURE 8,

FIGURE 17 is a front View of the plate of FIGURE 16,

FIGURE 18 is a front view of the plate of FIGURE 15,

FIGURE 19 is a front view of the plates of FIGURES l5 and 16 in assembled position,

FIGURE 20 is a cross-sectional view similar to FIG- URE l, but of a modification of the switch of the invention,

FIGURE 21 is a cross-sectional view taken along line 21-21 of FIGURE 20,

FIGURE 22 is a cross-sectional view taken along line 2222 of FIGURE 20, and

FIGURE 23 is a cross-sectional view taken along line 2323 of FIGURE 20.

One field of application for the acceleration responsive switch of the invention is in a safe arming system for a ballistic missile. In such a device, it is ofttimes desirable that the missile be fired unarmed from its launching platform, and that it be armed only if it has attained a predetermined distance from its original starting position, so that it can be reasonably certain to reach its objective,

another switch plate ice and thus not return back to the vicinity of the launching area in armed condition. The device of the invention is of such nature that it will actuate a switch, connected into an appropriate arming circuit, only after the vehicle in which the device is mounted has travelled the required distance. The unit integrates actual acceleration with the distance flown.

As seen in FIGURE 1, the acceleration switch 1 comprises a generally rectangular shaped housing 3 provided with an internal chamber 5. The housing 3 is closed at each end by cover plates 14 and 16. Centrally mounted within the housing cavity 5 is a shaft 2, which is journalled at each end into bearings 18 and 21) in the end plates 14 and 16, respectively.

The shaft 2 is threaded at 24 along the major length thereof, and at one end of the shaft there is fixedly mounted a gear 26, and at the opposite end of the shaft is fixedly mounted a weighted disc or flywheel 22. The form shown of a threaded or jack screw shaft 2 is wellknown in the art, and is generally termed a low friction screw device.

Threadedly mounted on the shaft 2 on the threaded portion 24- is a travelling nut 4 of generally cylindrical form as shown in FIGURE 2. The travelling nut is provided on one side with an extension 6 terminating in an enlarged head or bearing 8. Fixedly mounted within the chamber 5 of the housing 3 is a guide track 10 having a guide slot 12 opening inwardly. The headed end 8 of the nut extension 6 is constrained to move within this guide track 12. Thus, when the acceleration switch is mounted in a vehicle moving in the forward direction as indicated by the arrow in FIGURE 1, and upon acceleration of that vehicle, the traveling nut 4, working against the inclined plane of the threaded portion 24 of the shaft 2 will impress a torque on the shaft 2. The shaft 2 will be caused to rotate and since the nut 4 is restrained from rotation with the shaft by the guide track 12, it will travel towards the weighted disc 22.

From the well-known equations of rotational motion, we find that the torque T on the screw=al; but since T :wg tan 6 (of helix L) and therefore a=2wg tan 0Kg (Where K is a constant containing the design constants of the helix L, the weight of the nut W and I of the nut). The acceleration a, then, of the wheel or disc 22 is proportional to the linear acceleration (a) applied by the nut 4 to the shaft 2, and the veloctiy of rotation to is the first integral of (a). The second integral of (a) is the displacement 20.

The velocity of the nut is proportional to the velocity of the vehicle attained and the displacement of the nut along the shaft is proportional to the displacement of the vehicle from its starting point. By measuring the dis placement of the nut, the displacement of the vehicle is determined. Therefore, if it is desired that the switch be actuated after the attainment of a certain total displacement of the vehicle in which the unit is mounted from a starting point, it is-necessary only that the length of the lead screw or threaded portion 24 of the shaft 2 between the starting position for travel of the nut 4 and the section line 22 in FIGURE 1 (and therefore also the starting position of the nut 4, itself) be made proportional to the displacement of the vehicle to be attained, before the switch 52 is to be actuated.

Mounted within the chamber 5 and at the left end of the guide track It (as viewed in FIGURE 1) upon a shoulder 59 is a switch plate 58. The switch plate 58 is caged or held in its position by a retaining plate 60 appropriately fastened to the shoulder 59 which permits rotational movement only of plate 58. The switch plate 58 is formed ensues? Y3 CD with an extending projection or tab 7 positioned in the path of motion of the nut 4.

After the vehicle has travelled a total distance from its 7 starting point to a desired position where the switch 52 is to be actuated, the nut 4 has travelled along the threaded portion 24 of shaft 2 until it arrives at a position with the head 8 opposed to the extension or tab 7t) on the switch plate 58. This position is more clearly shown in FIG- URE 2. Upon further movement of the nut 4 to the left as viewed in FIGURE 1, and since the nut 4 will be constrained to linear motion, it will be free to rotate with the shaft 24 which will then be driven by the flywheel 22. The prior rotation of the flywheel stores sumcient energy to rotate the nut 4 clockwise (as viewed in FIGURE 2) until extension 6 strikes the extension 70. The switch button 54 of the switch 52 projects through an opening 56 in the switch plate 58. When the extension 70 is struck by the extension 6, the switch plate 58 is caused to rotate by the rotation of the nut t, and the latch 74 is depressed to permit further rotation of plate 58. Immediately thereafter the switch button 54 becomes depressed by the switch plate 58, thus actuating the switch 52. The dimensions of the nut 4 and the flywheel 22 in relation to the positions of the switch plate 58 and switch 52, are such that the nut 4 will reach the end of its travel while still actuating the switch button 54 via the switch plate 58.

In order to re-set the device, if it is intended to be reused, there is provided a re-setting mechanism shown in FIGURES 1 and 3. In the cover plate 14 there is provided a bore 42 which is sealed by a cover 46 mounted within an opening leading to the bore 42, and fastened to the end plate 14 by an appropriate fastening 1$. A shaft 34 projects into the bore 42 of the end plate 14 and has an end 40 provided with a slot 44. The other end 34!- of the shaft slides within a bore 36 in a hub or boss 32. The bore 36 is enlarged to accommodate a spring 38 which bears at one end against a small pinion gear 28 afirxed to the shaft 30, and at its other end against a shoulder in the bore 36.

In order to re-set the device, the cover plate 46 is removed and the spring 38 will urge the pinion 28 to the right as shown in FIGURE 3. The pinion 28 will then engage with the gear 26 mounted at the right end of the shaft 2. By inserting an appropriate tool into the slot 44 of the shaft 30, the pinion 28 and hence the gear 26 can be rotated to cause the nut 4- to rotate and carry with it the switch plate 58. The switch plate will be rotated until it is in alignment with the guide channel 12. The switch plate 58 is provided with an enlarged opening 72 through which the extension 6 of the nut 4 can pass. In this position, also, the disc 58 will be latched by a spring loaded latch '74; (as shown more clearly in FIGURES 4 and 5) and the switch button 54 will project through the opening 56 and no longer be depressed. As soon as the shaft 2 has been rotated to bring the nut 4 and the switchplate 58 into this position, the nut 4 will enter the guide channel 12 upon further rotation of the shaft 2. The pinion 28 will then be rotated to carry the nut 4 to its initial position (or a desired starting position) on the far right end of the shaft 2 as viewed in FIGURE 1, and the shaft 3% will then be depressed to bring pinion 28 out of engagement with gear 26 and the cover plate 46 again remounted.

As shown in FIGURE 4, the spring loaded latch '74 is pivotally mounted on a shaft or roll pin '76. The latch is undercut as at the surface 78 to prevent the latch from ramming the retaining ring 60 when in locked position, and also to permit the latch to be fully seated in the cavity 80 formed in the retaining ring 6h. A spring 90 urges the latch outwardly. The latch is shown in FIG- URE 4 in up or latched position, i.e., with latch 74 extending into an opening 82 in the switch plate 58 to retain it in re-set position. At this time the switch 52 is open and the nut 4 is either in the process of being reset or d has travelled back to re-set position since the nut is lined up with the track 12.

As shown in FIGURE 5, the latch is in closed position having been urged within cavity 82 by rotation of the switch plate 53 in the clockwise direction as viewed in FIGURE 2. In this position the output switch has been triggered and the distance switch has completed its run.

In the event the vehicle is decelerate-d prior to output switch action, then a reversely acting torque would be placed on nut 4, tending to stop it; and under continued deceleration, the stored energy in flywheel 22 would be released to keep nut 4 moving toward the distance output switch. As long as the vehicle has a minimum forward velocity at the coincident distance point, the output switch will function. The magnitude of this minimum velocity is a design function governed by the energy required to throw the output switch and is thereby a further safing function, guarding against the partial performance type malfunction of the missile engine.

Where it is desired to have the acceleration switch actuate two switches, the arrangement shown in FIGURE 6 can be employed. Tie acceleration switch of FIG- URE 6 comprises a rectangular housing 1% which is provided with the internal chamber Th5. The housing W3 is closed at each end by cover plates 114 and 116. Centrally mounted within the housing cavity 165 is the shaft 1 32, which is journalled at each end into the bearings 111% and 12% in the end plates ltlld and 116, respectively. The shaft M2. is threaded as at 124 throughout the major portion of the length thereof. At one end of the shaft 1692 is the reset gear 126, and at the opposite end of the shaft is the flywheel I22. Threadedly mounted on the shaft 1% is the travelling ball bearing nut 1% which is provided with the extension 1% and an enlarged head 1%. The head M3 travels within the guide slot 112 formed in the guide track 110. Operation of this device is entirely similar to that above-described in connection with FIGURES 1-5. In general, the shaft NZ will be caused torotate upon acceleration of the vehicle in which the device is mounted, and the traveliing nut 1%, being restrained from rotation with the shaft by the guide track will travel towards the disc 122 into which rotational energy is being stored. The switch plate arrangement in this embodiment diflers from that in the embodiment described above since two switches are to be actuated. As shown in FIGURES .6 and 7, the switching arrangement comprises a pair of switch plates 2% and 292. These switch plates are in sector form as shown in FIGURE 7, and the plate 23% is formed with a guide track portion 2% into which is fitted the inner edge of the plate portion 2%. The plate C-tltl has a depending flange 222, and the switch plate 202. has the depending flange 224. These flanges 222 and 224 serve to simultaneously actuate the two switches 25%) and 252. The switch plate 2% is provided with a pin T74 extending outwardly therefrom. FEGURE 7 shows the switch in re-set position at the instant that the travelling nut 164 has reached the end of its travel along the shaft 162. This position is shown in dotted lines in FIGURE 6 and also in FIGURE 7. In this position the extension 1496 comes out of its guide channel 112 and commences to rotate clockwise as viewed in FIGURE 7, until it rotates one revolution and contacts pin T74. As soon as clockwise rotation of the pin 174 and the switch plate 2% is commenced, the plate 2th) rotates approximately within the slot 226 to actuate the switches 25% and 2.52 by depressing their switch levers and 2%, respectively. When the plate 2% is caused to rotate 90, its depending flange 222 is placed in alignment with the flange 224 of the plate 2%, so that a complete raceway is formed to retain the switches in actuated position. It shouid also be noted that the latch lever 2% is similarly constructed to the latch 74 described in connection with FIGURES l--5. The latch 32% latches against the surface 219 on the switch plate 2%. Re-setting of the acceleration switch of FIGURES 6 and 7 is done in the same manner as described in the first described embodiment, employing the gears 126 and 128.

In the embodiments of the invention above-described, the weight to inertia ratio of the flywheel employed can be improved by fixing the screw in a stationary position and making the entire cylindrical element in which the nut is guided into the flywheel. In addition, the switching arrangement of the embodiment of FIGURES 6 and 7 presents problems of resonance as regards the spring switch actuators. With noise spectrums in the range of 050 kc., the switch actuators may be caused to vibrate in such manner that the switches are either actuated prematurely or are not actuated at the instant desired. In this connection, the embodiments of FIGURES 8-19 can be employed. In the embodiment of FIGURE 8 the distance switch 300 comprises a two-part housing 316 and 318. The housing encloses a flywheel 322 having end plates 311 and 313. The flywheel is rotatably mounted at 310 and 312 on a fixed shaft 302. The shaft 302 is threaded at 324 for the major portion of its length.

Movable within the chamber 305 formed within the flywheel 322, and in threaded engagement with the threads 324 of shaft 332, is a seismic mass or ball-bearing nut 304 which is provided with an extension having a follower head 303 which is constrained to longitudinal movement Within a guide track 339 formed on the inner surface of the flywheel 322. Thus, upon acceleration of the device the nut 304 iscaused to translate with respect to the flywheel 322, this translation causing rotation of the flywheel 322 in view of the threaded mounting. The torque generated by the nut on the shaft 302 causes-the rotation of the flywheel, and the nut 304 will progress down the length of the threaded portion 324 of the screw shaft 302 until it runs off of the threaded portion 324 and is located at the non-threaded portion 325. The nut 304 will then free-wheel until the pin 306 enters the opening 307 in the end plate 311 of the flywheel. When the pin comes through the opening 307, it will actuate the switching plates 340 and 342 mounted on the hub 317 of the housing section 316.

FIGURES 8 and 11 show the plates 340 and 342 in aligned position with the switches unactuated. The connector plug 362 has a series of leads 360 running therefrom to the contact ring 344. This contact ring 344 is provided with a series of spring finger contact elements 34-6, 348, 350 and 352. These spring contact elements bear upon the two switch disc plates 340 and 342. The reason for locating two pairs of switches (i.e., switch 346 and 35h constitute one pair; and switches 348 and 352 constitute a second pair) on orthogonal relationship to each other is that when the switches are subjected to vi-' bration. along any plane, the circuit cannot be opened. This is obvious since as soon as the spring switch finger on the right-hand side would lift due to motion from the left, the left-hand side would be forced into contact position; and conversely, when the left-hand switch finger lifts due to motion from the righthand side, vibration will pull the right one back into contact.

Referring now to FIGURES 15, 16, 17, 18 and 19, it is seen' that the plate 340 consists of a flat section provided on one side with the protruding pin 380 and on the other side with an abutment 382. The abutment 382 is appropriately fastened as by rivets 333 and 334 to the plate 340. This plate 340 and its abutment 382 faces the flywheel so that as the pin 3% protrudes through the opening 307, the pin 306 will eventually hit upon the abutment 332 and rotate the plate 340. Since the underside of the plate 340 is provided with a pin 380, and the plate 342 is provided with an arcuate slot 343 in which the pin 330 rides, pin 380 will move within the slot 343 until it reaches the end of the slot. At that time the switches will be actuated.

The switch disc 340 is provided on its circumference with a series of conductive and non-conductive surfaces. The recessed surfaces 384, 386, 387 and 388 are nonconductive, whereas the peripheral surfaces 390, 391, 392 and 393 are conductive. Similarly, the surfaces 371, 372, 373 and 374 of plate 342 are non-conductive; whereas the surfaces 375, 376, 377 and 378 are conductive. When the plate 340 is rotated so that the pin 380 contacts the end of the slot 343, the two plates will be in the relative position shown in FIGURE 19, with their conductive surfaces in alignment so that contact will be made with the spring finger contacts. Any further rotation of the nut 304 and its pin 306 caused by the inertia of the flywheel 322 will serve only to continue rotational movement of the two switch discs without misaligning them. Since the two switch discs in the aligned position of FIG- URE 19 present a continuous conductive circle wiping against the spring switches, a very reliable and permanent switch closure is obtained.

Re-setting of the switch of FIGURE 8 is accomplished by a means generally similar to that previously described. The pin 346 is first depressed and then rotated, which results in the gear 328 coming into engagement with and rotating the ring gear 329 on the flywheel 322. When the ring gear 329 is rotated, the captured nut 304 is also rotated. When the nut 304 is rotated, pin 306 will return the two switch plates to the position shown in FIG- URE 11, at which time the nut will be picked up on the threaded portion 324 and then returned to its re-set position. When the nut 304 has returned to re-set position, a caging mechanism shown in detail in FIGURE 9 acts retain the nut in its re-set position.

The caging mechanism referred to above consists of a pair of bar magnets 402 and 404 interconnected by a plate 400. When the nut 304 has travelled to the eX- treme right end of the screw 302, it is attracted to the magnet which then holds it with suflicient force to prevent rotation of the nut only until the desired minimum acceleration is reached. The caging mechanism also includes a mass 410 which is of such a weight that a minimum acceleration must first be exceeded before the flywheel can begin to rotate and before the magnetic attraction force will be overcome to permit rotation of the nut 304. This mass 410 slides within a sleeve 411 in the end plate 313 of the flywheel 322. The mass 410 is provided with an extending plunger 412. The mass 410 is also spring urged to the right as viewed in FIGURE 8 by a spring finger 406. The spring finger 406 is mounted by the mounting 408 to the inner surface of the flywheel 322. As indicated above, the spring rate of the spring 406 and the mass 410 are so chosen that a minimum acceleration must first be experienced by the vehicle before the mass will begin to translate to the left to release the flywheel for rotation. The plunger 412, when in its extreme right position as viewed in FIGURE 8, will bear against a cam plate 413 so that frictional forces will serve to retard or prevent rotational motion of the flywheel 322 in addition to the magnetic attraction force on the nut 304. If at any time during the travel of the vehicle acceleration falls below the desired minimum acceleration (i.e., such as might occur if the engine flames out), the mass 410 will again be urged into its caging position to retard the motion of the flywheel and thus prevent further motion of the nut 304.

An electrical reset signal is obtained by employment of the plunger 412 and the cam disc 413. As shown in FIGURES 12 and 13, the cam disc 413 is provided with a contact strip 414. This contact strip 414 is a spring loaded contact strip and is opposed to the contact button 420. The contact strip 414 is riveted to the plate 413 by the rivets 416 and 418. The rivet 416 also serves as an electrical connecting post for the lead 419. The opposite lead 422 is connected to contact button 420 as shown in FIGURE 14. Thus, when the device is in the re-set or caged position, the plunger 412 will bear against the contact strip 414 and close a switch circuit. This switch circuit may be so connected to flash a light or give an audible indication of the re-set or caged position. The

caging mechanism also serves to prevent vibrations during shipping of the device and also as an additional means of absorbing shock to the device when it is in its re-set position.

Where the distance switch is to operate only over a very short distance, the flywheel may be incorporated as part of the ball bearing nut itself. Such a device is shown in FIGURES 20, 21, 22 and 23. As shown in FIGURE 20, the distance switch Sill. comprises a housing 503 which contains a pair of lead screws and 564 mounted within a framework or standard 595. Since a pair of similar shafts 502 and 504 are shown together with the ball bearing nuts 5% and 508 which have their own flywheels 51d and 512, respectively, further description will be limited to the lower arrangement around shaft 504, it being understood that the upper shaft 592 and nut 566 operate similarly in connection with its switches.

Since the device is operating over a very short distance, a large amount of flywheel is not needed. Therefore, the flywheel formed by the enlarged flange 512 will be sufiicient to store enough energy to continue the rotation of the nut 508 after it leaves the threaded portion 520 of the shaft 564 and enters the unthreaded portion 522. Operation of the device is similar to the devices previously described in that upon acceleration in the direction of the arrow as shown in FIGURE 20, the nut 5% will work its way down the threaded portion of the shaft 504 until it reaches the portion 522. In this position the nut will continue its rotation due to the energy stored in its flywheel portion 512 in such manner as to bring the nut 7 against the switch actuating leaves 524 and 526. These switch actuating leaves will depress the switch operating buttons 528 and 532 of the switches 534i and 53 i, respectively.

Re-setting of the nut 568 is accomplished by rotating the gear 54th which is constantly in mesh with gear 542 mounted on the shaft 504. The shaft 504 will then be rotated until the nut St)? is brought to the extreme righthand position as viewed in. FIGURE 20.

A caging system is provided to hold the nut in the upper position, and this caging system includes a torsion bar 556) which is pivotally mounted within the standard 505 by the stub shafts 552 and 554. A depending lug or stop 556 is located on the torsion bar 5563 and this lug is located in the path of a reset mass 558 which is spring urged as by spring 569 into contact therewith. As soon as the desired minimum acceleration is reached, the mass 558 is set back to release the lug 556 and permit the torsion bar to return to a neutral position shown in dotted lines in FIGURE 21. The torsion bar is urged into this neutral position'by a spring mount, wherein the spring 570 (see FIGURE 22) is mounted with one leg of the spring inserted in the stub shaft 554, and the other end of the spring inserted in a stop lug 572 affixed to the standard 5435. It is thus seen that the torsion bar when in the position shown in solid lines in FIGURE 21 serves as a friction brake to prevent rotation of the nuts 5% and 506 while they can be reset. In the operating position with the torsion bar returned to a neutral position, the shafts 592 and 504- are prevented from rotation by their gear arrangement so that the nuts can travel down the shaft to actuate the switches.

The aceleration switch just described will cause the actuation of a switch after the vehicle in which the unit is mounted has travelled a predetermined distance. It will be understood by those skilled in the art that various modifications may be made while still coming within the scope of the invention as set forth in the appended claims.

What I claim is:

1. An acceleration integrating switching device subjected bodily to acceleration, comprising: a housing, said housing containing a partially threaded shaft and a nut thereon, means cooperating with said housing for constraining said nut to translational movement with respect to said shaft for a portion of its travel upon said shaft,

switch actuating means mounted within said housing and disposed adjacent to said shaft, means upon said nut for activating said switch actuating means, said nut being arranged to translate a substantial distance along said shaft when said housing is bodily subjected to acceleration forces acting in a direction parallel to said shaft, the switch actuating means being activated when said nut has travelled a predetermined distance along said shaft proportional to the distance displaced by the housing during the acceleration of the device.

2. An acceleration integrating switching device subjected bodily to acceleration, comprising: a housing, said housing containing a partially threaded shaft and a nut thereon, energy storage means mounted upon said shaft, means cooperating with said housing for constraining said nut to translational movement with respect to said shaft for only a portion of its travel upon said shaft, said energy storage means being so arranged as to impart its stored energy to rotate said nut after it has left the area of said shaft wherein it is constrained to translational movement, switch actuating means mounted within said housing and disposed adjacent to said shaft, and means upon said nut for activating said switch actuating means, said nut being arranged to translate a substantial distance along said shaft when said housing is bodily subjected to acceleration forces acting in a direction parallel to said shaft, the switch actuating means being activated when said nut has travelled a predetermined distance along said shaft proportional to the distance displaced by the housing during the acceleration of the device.

3. An acceleration integrating switching device subjected to bodily acceleration, a housing, said housing containin g a partially threaded shaft and a nut thereon, means cooperating with said housing for constraining said nut to translational movement with respect to said shaft for a portion of its travel upon said shaft, switch actuating means mounted within said housing and disposed adjacent to said shaft, means upon said nut for activating said switch actuating means, a resetting means mounted within said housing adjacent to and cooperating with said shaft to deactivate said switch actuating means and return said nut to its starting position, said nut being arranged to translate a substantial distance along said shaft when said housing is bodily subjected to acceleration forces acting in a direction parallel to said shaft, the switch actuating means being activated when said nut has travelled a predetermined distance along said shaft proportional to the distance displaced by the housing during the acceleration of the device.

4. An acceleration integrating switching device subjected to bodily acceleration, comprising: a housing, said housing containing a partially threaded shaft and a nut thereon, energy storage means mounted upon said shaft, means cooperating with said housing for constraining said nut to translational movement with respect to said shaft for a portion of its travel upon said shaft, said energy storage means being so arranged as to impart its stored energy to rotate said nut after it has left the area of said shaft wherein it is constrained to translational movement, switch actuating means mounted within said housing disposed adjacent to said shaft, means upon said nut for activating said switch actuating means, and a resetting means mounted within said housing adjacent to and cooperating with said shaft to deactivate said switch actuating means and return said nut to its starting position, said nut being arranged to translate a substantial distance along said shaft when said housing is bodily subjected to acceleration forces acting in a direction parallel to said shaft, the switch actuating means being activated when said nut has travelled a predetermined distance along said shaft proportional to the distance displaced by the housing during the acceleration of the device.

5. The device of claim 3 wherein said re-setting means comprises a first gear means on said shaft, juxtaposed second gear means adapted to be brought into driving relationship with said first gear means to rotate said shaft and return said nut to its starting position.

6. The device of claim 4 wherein said re-setting means comprises a first gear means on said shaft, juxtaposed second gear means adapted to be brought into driving relationship with said first gear means to rotate said shaft and return said nut to its starting position.

7. The device of claim 1 wherein said switch actuating means comprises at least one rotatably mounted plate-like member arranged to be rotated by the activating means upon said nut into switch engaging position.

8. The device of claim 7 including latching means for retaining said plate in non switch engaging position and in alignment to receive said activating means upon said nut.

9. The device of claim 2 wherein said switch actuating means comprises at least one rotatably mounted plate-like member arranged to be rotated by the activating means upon said nut into switch engaging position.

10. The device of claim 9 including latching means for retaining said plate in non switch engaging position and in alignment to receive said activating means upon said nut.

11. An acceleration integrating switching device subjected to bodily acceleration, comprising: a housing, said housing containing a partially threaded shaft and a nut thereon, means cooperating with said housing for constraining said nut to translational movement with respect to said shaft for a portion of its travel upon said shaft, switch actuating means mounted within said housing and comprising a pair of segmented intermeshed plate-like members annularly disposed about said shaft, and means upon said nut for contacting one of said plate-like members to rotate said pair of members into switch engaging position, said nut being arranged to translate a substantial distance along said shaft when said housing is subjected to acceleration forces acting in a direction parallel to said shaft, the switch actuating means being activated when said nut has travelled a predetermined distance along said shaft proportional to the distance displaced by the housing during the acceleration of the device.

12. An acceleration integrating switching device subjected to bodily acceleration comprising: a housing, said housing containing a partially threaded shaft and a nut thereon, energy storage means mounted upon said shaft, means cooperating with said housing for constraining said nut to translational movement with respect to said shaft for a portion of its travel upon said shaft, said energy storage means being so arranged as to impart its stored energy to rotate said nut after it has left the area of said shaft wherein it is constrained to translational movement, switch actuating means comprising a pair of segmented intermeshed plate-like members annularly disposed about said shaft, means upon said nut for contacting one of said plate-like members to rotate said pair of members into switch engaging position, said nut being arranged to translate a substantial distance along said shaft when said device is subjected to acceleration forces acting in a direction parallel to said shaft, the switch actuating means being activated when said nut has travelled a predetermined distance along said shaft proportional to the dis tance displaced by the housing during the acceleration of the device.

13. An acceleration integrating switching device subjected to bodily acceleration comprising: a housing, said housing containing a partially threaded shaft and a nut thereon, means cooperating with said housing for constraining said nut to translational movement with respect to said shaft for a portion of its travel upon said shaft, switch actuating means mounted within said housing and disposed adjacent to said shaft, means upon said nut for activating said switch actuating means, caging means adapted to retain said nut in starting immobile position until a predetermined degree of acceleration is attained, said nut being arranged to translate a substantial distance along said shaft when said device is subjected to acceleration and acting in a direction parallel to said shaft, the switching actuating means being activated when said nut has travelled a predetermined distance along said shaft proportional to the distance displaced by the housing during the acceleration of the device.

14. An acceleration integrating switching device subjected to bodily acceleration, comprising: a housing, said housing containing a partially threaded shaft and a nut thereon, energy storage means mounted upon said shaft, means cooperating with said housing for constraining said nut to translational movement with respect to said shaft for a portion of its travel upon said shaft, said energy storage means being so arranged as to impart its stored energy to rotate said nut after it has left the area of said shaft wherein it is constrained to translational movement, switch actuating means within said housing and disposed adjacent to said shaft, means upon said nut for activating said switch actuating means, caging means adapted to retain said nut in starting immobile position until a predetermined degree of acceleration is attained, said nut being arranged to translate a substantial distance along said shaft when said device is subjected to acceleration forces exceeding said predetermined degree of acceleration and acting in a direction parallel to said shaft, the switch actuating means being activated when said nut has travelled a predetermined distance along said shaft proportional to the distance displaced by the housing during the acceleration of the device.

15. The device of claim 13 wherein said caging means includes a means for magnetically holding said nut against motion until said predetermined degree of acceleration is exceeded.

16. The device of claim 14 wherein said caging means includes a spring loaded mass having means associated therewith for preventing motion of said nut until said predetermined degree of acceleration is exceeded.

17. The device of claim 16 wherein said energy storing means comprises a hollow flywheel rotatably mounted upon and substantially encompassing said shaft, said shaft being fixed in said housing, said spring-loaded mass being mounted upon said flywheel and having a probe portion extending therefrom to bear upon a surface offering frictional resistance to motion until the acceleration forces overcome said spring-mass loading on said probe portion.

18. The device of claim 16 including yieldably mounted brake means permitting motion of said nut when said predetermined degree of acceleration is exceeded, said springloaded mass cooperating with said brake means to arrest motion of said nut when said device experiences accelerations below said predetermined degree.

References Cited by the Examiner UNITED STATES PATENTS 2,427,239 9/47 Taylor 73-514 2,979,942 4/61 Allen 73-514 3,023,284 2/62 Lautzenhiser ZOO-61.53 3,666,540 12/62 Severance 75-5()3 BERNARD A. GILHEANY, Primary Examiner. MAX L. LEVY, ROBERT K. SCHAEFER, Examiners. 

1. AN ACCELERATION INTEGRATING SWITCHING DEVICE SUBJECTED BODILY TO ACCELERATION, COMPRISING: A HOUSING, SAID HOUSING CONTAINING A PARTIALLY THREADED SHAFT AND A NUT THEREON, MEANS COOPERATING WITH SAID HOUSING FOR CONSTRAINING SAID NUT TO TRANSLATIONAL MOVEMENT WITH RESPECT TO SAID SHAFT FOR A PORTION OF ITS TRAVEL UPON SAID SHAFT, SWITCH ACTUATING MEANS MOUNTED WITHIN SAID HOUSING AND DISPOSED ADJACENT TO SAID SHAFT, MEANS UPON SAID NUT FOR ACTIVATING SAID SWITCH ACTUATING MEANS, SAID NUT BEING ARRANGE TO TRANSLATE A SUBSTANTIAL DISTANCE ALONG SAID SHAFT WHEN SAID HOUSING IS BODILY SUBJECTED TO ACCELERATION FORCES ACTING IN A DIRECTION PARALLEL TO SAID SHAFT, THE SWITCH ACTUATING MEANS BEING ACTIVATED WHEN SAID NUT HAS TRAVELLED A PREDETERMINED DISTANCE ALONG SAID SHAFT PROPORTIONAL TO THE DISTANCE DISPLACED BY THE HOUSING DURING THE ACCELERATION OF THE DEVICE . 